Two Master theses on the biodiversity of soil algae available starting from March 1, 2023 (Project SoilAlgae 2.0)

Open Ph.D. Position

There are two Master theses available at the University of Göttingen's Collection of Algal Cultures (SAG), one of the world's largest collections of living algal cultures. Both theses are part of a new research project funded by the German Research Foundation (DFG). The project investigates the changes in the diversity of soil algae under different land use, bo­th in forests and grassland (

Biodiversity Exploratories, DFG-SPP 1374). The results of both theses are to be combined into a synthesis of the factors that determine the biodiversity of soil algae. Both works will be co-supervised by a Ph.D. student position in the project. Therefore, good teamwork skills are expected.
One thesis preferably deals with study sites in the forest. Besides samples of topsoils, surface samples of wood substrates, i.e., tree bark and dead wood, are also included. The other thesis focuses on grassland. ­

Joint multi-site experiments (FOX in forests, LUX/REX in grassland) are also being worked on in both studies. The effects of different land use, such as the opening of the canopy in forests with deadwood enrichment or removal, grassland fertilization, and disturbance of the soil surface, on the biodiversity of soil algae and cyanobacteria, are investigated.

  • The project will start by March 1, 2023, and is funded for three years.


  • Good knowledge of the statistical and graphical analysis of DNA sequence data (e.g., programming languages R or Python)
  • Experience in laboratory work with molecular techniques, DNA extraction, PCR, and DNA sequencing
  • Experience with microscopic analyses of algae and/or other microorganisms, such as isolation of algal cultures

Project description:
"Changes in the genetic biodiversity of algae and cyanobacteria in terrestrial surface environments of forest and grassland under the influences of land use and vegetation (Soil Algae 2.0)"
Algae (photoautotrophic protists) and cyanobacteria are important components of soil microbial communities. Due to their photoautotrophic lifestyle, soil algae and cyanobacteria provide multiple inputs in the form of energy, carbon, and oxygen. In the soil, they are closely linked with other non-phototrophic protists and bacteria to form functional networks of varying composition. Due to their broad biochemical diversity of pigments, photosynthetic reserve products, cell walls, mucilage, fatty acids, and other bio-active compounds, they have numerous beneficial effects on the soil.
The actual relevance of the biodiversity of soil algae and cyanobacteria for the complex processes in the soil has so far remained underestimated. This is because their biodiversity is insufficiently understood so far. Therefore, we will comprehensively assess the biodiversity of soil algae and cyanobacteria with a high taxonomic and genotypic resolution to find out how it is influenced and determined.
Working hypotheses:

  • Different vegetation, land use, and intensities of land use influence the genetic diversity of soil algae and cyanobacteria
  • The biodiversity of algae in forest surface soils is closely related to that of algal communities on the surfaces of deadwood and tree bark
  • Greenland generally has a higher diversity of soil algae and cyanobacteria than forest soils
  • Mechanical disturbance and fertilization have a negative influence on the phototrophic diversity of soil surfaces
  • State-of-the-art next-generation sequencing (NGS) methods and modern bioinformatics methods allow a comprehensive assessment of the biodiversity of photoautotrophic microorganisms in the soil at the genotypic level and deepen our knowledge of the phylogenies of these organisms

Laboratory methods:

  • Amplicon-based metabarcoding using the 23S UPA marker (Illumina Miseq (2x300 bp, paired-end)) for eukaryotic algal lineages and cyanobacteria, and ITS2 rDNA preferentially amplified for green algae are employed to capture the genetic biodiversity.
  • Long reads from amplicons (PacBio) of chloroplast and nuclear-encoded markers will be used to elucidate the phylogenetic relationships of soil algae and cyanobacteria.

Link to previous project:

SoilAlgae (2008 - 2011)
Please send your CV and a letter of motivation highlighting your lab experience as an e-mail.
Prof. Dr. Thomas Friedl [
Georg-August-Universität Göttingen
Albrecht-von-Haller-Institut der Pflanzenwissenschaften
Experimentelle Phykologie und Sammlung von Algenkulturen (EPSAG)